This invention pertains to a sine bar gage set of a type used, for example, by technicians and others in disposing a work piece to be trimmed, cut or milled at a particular angle, and more particularly to such a set of gage elements where each is marked with indicia directly identifying the angle, i.e. marked with the angle thereon, and an assembly maintaining such elements in a predetermined organization.
Sine bars measure angles accurately and locate work at a desired angle to some other reference surface or plane. They frequently are used in conjunction with some true surface such as a horizontal surface from which measurements can be taken, preferably a thoroughly clean surface plate. The exact degree of angularity which a five-inch or ten-inch sine bar makes with a plane surface has in the past been obtained by calculating or otherwise determining the precise vertical height of one end. The correct combination of linearly measured gage blocks placed beneath the elevated end of the sine bar provides the appropriate height to establish the calculated angle desired. A technician is required either to calculate through trigonometric functions the exact amount of linear gage blocks which are to be employed or refer to a table of constants to provide the height for the various angles.
As will be readily evident from the foregoing description, when it is desired to tilt the sine bar at a given angle, selection of the right combination of linearly measured gage blocks will be necessary to be inserted beneath the elevated end of the sine bar. In selecting the height of the gage blocks using the foregoing arrangement it is further evident that the possibility of error is significant due to the need for calculations of the trigonometric function or in using a reference table or chart.
As disclosed herein a set of direct-reading sine bar gages has been provided in which each of the gage elements is marked with a number corresponding to the associated angle of elevation of the sine bar when that particular element is disposed beneath the sine bar. Accordingly, when the technician is seeking to elevate the sine bar to a particular angle the technician needs only to inspect the various gage elements to determine which of them is marked with a number corresponding to the angle which he desires.